Darks at different time baffled..

[EzyStyles]

Hi Guys,

Since the clouds rolled in, ive decided to take a few dark frames tonight. The first dark frame was taken at 7pm and the second was taken at 11pm. I know due to tempreture variations, this will change but why is it that my first dark frame is so green? I couldnt change that dramatically within 4 hours time? ive also noticed the amp glow is brighter later in the night? anyone got an example of their darks?

both were 5mins expo at ISO 800.

cheers.

[[1ponders]]

How long had the camera been turned on before you took your first dark Eric? And had the camera been taking other darks up until the last one? Also what time lag between successive darks?

[EzyStyles]

howdy paul, probably after 10 mins of turning the camera on. yes, it was continuously taking darks at different time and iso settings. i wouldn't know since they were all taken at differnt time and iso settings throughout the night up until ive decided to take another 5 mins/iso800 shot for comparision.
cheers.

[[1ponders]]

If you can turn your camera on for half an hour before starting and see how much difference there is. Also if you are continually taking photos without a break between images then your amp will not have a chance to cool down.

[EzyStyles]

arh that makes sense. never knew the amp has to be cooled down. thanks paul.

[[1ponders]]

It doesn't have to be cooled down as such but if you are taking images continuously then it will generate more heat than if you take an image and then wait 30, then take another one. When collecting lights and darks I will wait 30 sec before taking the next image. In a normal course of a nights images I will take a series of lights then a series of darks, but I will always spend at least 30 to 30 min with the camera turned on (AC powered) taking focus shots or sample shots just to get the camera up to temperature.

[h0ughy]

LOL would have been pointless me posting my 350D darks

look here (http://www.iceinspace.com.au/forum/showthread.php?t=20283&highlight=cooled+350D) for a refresher

and here (http://www.iceinspace.com.au/forum/showthread.php?t=20264&highlight=cooled+350D)

[EzyStyles]

NNNNNooooooOOOOoooOOooooo......!!!
me want it.....

[EzyStyles]

thanks paul. i normally give it 10 second between each dark frame but my flats are taken one after another straight away.

[h0ughy]

Sure;):lol: - lets see 1200 for the camera and 1500 for the refit, gee thats more than a 40D????:whistle:

[[1ponders]]

Flats it shouldn't matter as they are so short compared to your lights and darks.

btw 30 to 30 min should have been 20 - 30 min